The present invention relates to improvements in plastic sliders for opening and closing plastic reclosable fasteners on plastic bags and the like and particularly to improvements in one-piece "gull wing" type foldable plastic sliders for profiled plastic reclosable fasteners on plastic bags.
Plastic zippers with sliders are well known in the art. The plastic zippers have profiles and include a pair of male and female fastener elements in the form of reclosable interlocking rib and groove elements with a slider for opening and closing the rib and groove elements. In the manufacture of thermoplastic film bags, a pair of these male and female fastener elements extend along the mouth of the bags and these male and female elements are adapted to be secured in any suitable manner to the flexible walls of the thermoplastic film bag. These elements may be integral marginal portions of such walls or they may be extruded separately and thereafter attached to the walls along the mouth of the bag. A method of continuously providing such a fastener on the thermoplastic film is disclosed in U.S. Pat. No. 3,462,332.
The sliders for opening or closing the reclosable fasteners are essentially U-shaped and adapted to be assembled with the fastener or zipper by an endwise assembly or by a relative transverse maneuver. In some instances the sliders are formed of multiple parts and assembled on the zipper. The assembly may be simplified if the slider is formed of one part and the sides are foldable into position when assembled on the zipper. Examples of foldable plastic sliders are disclosed in the related applications referred to below.